Re: [Qemu-devel] [PATCH v10 2/7] hw/ptimer: Perform tick and counter wrap around if timer already expired

[Dmitry Osipenko]

Hi Peter,

10.01.2016 03:44, Peter Crosthwaite пишет:
> On Sat, Jan 9, 2016 at 9:39 AM, Dmitry Osipenko <address@hidden> wrote:
[cut]
> > In addition, there is no reason to keep expired timer tick deferred, so
> > just perform the tick from ptimer_get_count().
[cut]

I noticed an issue here... The problem is that device reset invokes 
ptimer_stop() that invokes ptimer_get_count() that might cause the tick after 
reset, i.e. bogus bh would be invoked after QEMU reset. I have reproduced that 
issue.

The solution might be to introduce ptimer_reset() that would stop QEMU timer and 
reset delta/load/period without invoking ptimer_get_count. And of course all 
devices should be updated to use new ptimer_reset() prior to "Perform tick and 
counter wrap around if timer already expired" patch, but that's not an issue I 
suppose. Please let me know if you have any objections, I'm leaning to do it in V11.

void ptimer_reset(ptimer_state *s)
{
    timer_del(s->timer);
    s->enabled = 0;
    s->period_frac = 0;
    s->period = 0;
    s->delta = 0;
    s->limit = 0;
}

--
Dmitry